Rules of exponents come in hand here.
Multiplication rule: a^m x a^n = a^ m+n
Division rule: a^m / a^n = a^m-n
Negative exponent: a^-m = 1/a^m; 1a^-m =a^m
So it would be (-3)^7+5 / (-3)^-2; (-3)^12 / (-3)^-2; (-3)^12 x (-3)^2; (-3)^14
The answer is (-3)^14. If you multiply it out it is 4,782,969.